Many researchers have suggested that get passives are ambiguous. For instance, Reed (2011) says that get passives are ambiguous between three different structures and interpretations:
(1) That child got hurt.
a. Verbal passive; much like a be passive.
b. Control; equivalent to That child got herself hurt, but with unpronounced PRO instead of herself.
c. Adjectival passive: hurt is an adjective (get can take adjectival complements, as in That child got sick.)
I focus on the verbal passive and the control structure here. The control structure is supposed to have the surface subject interpreted as something like an agent; as such, it can be modified by adverbs like deliberately (Lasnik and Fiengo 1974):
(2) I think that John deliberately got hit by that truck, don't you?
However, there is some reason to doubt the general availability of a control structure for get passives. First, notice that the following sequence makes sense and is not contradictory:
(3) That truck hit Marvin, but Marvin didn't get himself hit by that truck.
This is because the get passive with pronounced himself asserts more than just the corresponding active (or be passive): in addition to the truck hitting Marvin, Marvin did something to bring that hitting event about. So a truck hit Marvin can be true without Marvin got himself hit by a truck being true.
So, if any given example of a get passive could have a control analysis, we would expect the same non-contradictory pattern. This is not the case, however. The following is a contradiction, just like the corresponding sentence with a be passive:
(4) That truck hit Marvin, #but Marvin didn't get hit by that truck.
(5) That truck hit Marvin, #but Marvin wasn't hit by that truck.
Adding deliberately makes the sentence non-contradictory again:
(6) That truck hit Marvin, but Marvin didn't get hit by that truck deliberately.
From this it appears that the control (agentive) interpretation of a get passive is not generally available, but can only be brought about by the addition of something, like deliberately. Without some such element, a get passive is truth-conditionally equivalent to the corresponding active sentence, just like a be passive.
It is also worth pointing out that get does not pattern with raising verbs in truth conditional equivalence, either. Haegeman (1985), for instance, analyzed get as a raising verb like seem. Note the following contrast, however:
(7) That truck hit Marvin, #but Marvin didn't get hit by that truck.
(8) That truck hit Marvin, but Marvin didn't seem to have been hit by that truck.
The raising verb seem adds additional assertive content and so negating it does not contradict a simple active. If get is a raising verb, it is apparently a semantically contentless one.
A second observation casts doubt on the idea that get plus deliberately should be analyzed like get with an overt anaphor. It seems to me that adverbs like deliberately are degraded when there is an animate by-phrase. In (2), above, that truck is inanimate and can occur with deliberately. Contrast that example with an animate by-phrase:
(9) I think that Marvin deliberately got hit by Mike Tyson.
The example in (12) is acceptable only where Mike Tyson is not agentive, but he simply collided with Marvin. Where the by-phrase cannot be so interpreted, it is degraded with deliberately:
(10) Marvin deliberately got injured (??by his co-worker).
(11) Beckham deliberately got suspended (??by league officials) in order to attend his sister's wedding.
(12) The children deliberately got separated (??by the teacher) from their group (??by the teacher).
Note that there is no incompatibility between get plus anaphor and an agentive/animate by-phrase:
(13) Marvin got himself injured by his co-worker.
(14) Beckham got himself suspended by league officials in order to attend his sister's wedding.
(15) The children got themselves separated from their group by the teacher.
This suggests that get plus deliberately is not the same thing as get plus anaphor, as the control analysis assumes (or at least as Reed's version of it does).
I will make one last observation, which is not obviously related to the ones above. This is that sentential subjects are not very good in get passives, although they are fine with be passives and with raising verbs:
(16) *That the world is round got ignored for centuries.
(17) That the world is round was ignored for centuries.
(18) That the world is round seems to have been ignored.
(19) *That the world is round got shown conclusively in 1522.
(20) That the world is round was shown conclusively in 1522.
(21) *That these nouns behave differently got expressed/captured by this formulation of the rule.
(22) That these nouns behave differently was expressed/captured by this formulation of the rule.
This doesn't seem to be a semantic restriction, since the fact that is fine:
(23) The fact that the world is round got ignored for centuries.
(24) The fact that Columbus miscalculated the circumference of the earth got mixed up with the incorrect notion that medieval Europeans thought that the world was flat.
Sentential subjects are also bad with extraposition it:
(25) *It got expected/insisted/reasoned/predicted that the Giants would win the World Series.
(26) It was expected/insisted/reasoned/predicted that the Giants would win the World Series.
Apparent PPs are fine, but they are probably NPs; this one was found on the internet: When I vacuum, under the bed gets cleaned too.
Haegeman, Liliane (1985), The Get-Passive and Burzio’s Generalization. Lingua 66: 53–77.
Lasnik, Howard, and Robert Fiengo (1974), Complement Object Deletion. Linguistic Inquiry 5: 535–571.
Reed, Lisa A. (2011), Get-Passives. The Linguistic Review 28: 41–78.