[9000]

No, because the point of the value of defending people no matter what is to protect against government overreach. The government has a significant asymmetry of power against its citizens (it can, you know, arrest or kill them), so there are legal limits placed on what the government can do to its citizens. It has to justify to a judge why it needs to infringe a citizen's rights (e.g. warrants for search or seizure), whereas citizens are assumed to be allowed access to information about the government, and the government has to make a case to keep it confidential (see: FOIA, FISA, security clearances, etc.). In addition to these legal limits, we have social norms, like the one you mentioned, to reinforce this adherence to citizens' rights. We must protect all defendants against the government in order to hold the government to proper processes. If we think the government should have been able to get an awful person, we need to change the laws going forward, not retroactively.

Additionally, selective enforcement is primarily a tool of corruption. The law is supposed to apply to everyone. If it doesn't, then those who enforce it get to selectively choose to not enforce it against themselves and only enforce it against their enemies. And, as we've said, the government has very disproportionate power against its citizens, so to give prosecutors, police, or other enforcers of the law very broad, rarely used precedents is extremely dangerous.