In the Netherlands, the police can hold your finger to the fingerprint reader on a device they confiscated (might need a court order, or might depend on circumstances if there is an imminent threat to life or something), but they cannot order you to work on your own prosecution in general. Why, then, you can be ordered to put your finger on the pad, I have no idea, but it has been ruled that you cannot be ordered to tell them a password.
Then again, the secret services have been allowed to order giving up passwords since forever.
The solution there is to set aside a few less-used fingers which, when applied to the scanner in sequence, tell it to perform a secure wipe. I'm left-handed so I use a few fingers on my right hand plus my left little finger for access, this leaves enough fingers for a fingerprint-directed wipe command:
left index followed by
left ring followed by
left middle => Wipe
There is bound to be an app or option in some AOSP-derived distribution for that, if not you got the idea here.
You will almost always use one or two fingers to unlock your phone due to the fingerprint readers position and the police might be intelligent enough to ask you to put that exact finger on.
In the Netherlands, the police can hold your finger to the fingerprint reader on a device they confiscated (might need a court order, or might depend on circumstances if there is an imminent threat to life or something), but they cannot order you to work on your own prosecution in general. Why, then, you can be ordered to put your finger on the pad, I have no idea, but it has been ruled that you cannot be ordered to tell them a password.
Then again, the secret services have been allowed to order giving up passwords since forever.