The tulku system transmits an office by identifying a child as the return of the person who held it. For most of its history the question of who could make that identification was internal to Tibetan Buddhism, a matter of the previous holder's instructions, of divination, of oracles, of senior lamas in the relevant lineage, and, for the largest lines, of confirmation by the Dalai Lama.
It is now a dispute between a religious tradition and a state.
The People's Republic of China issued State Religious Affairs Bureau Order No. 5 in 2007, requiring that reincarnations of living Buddhas be approved by the government, and asserting that recognitions made outside that process are invalid. The instrument invoked as precedent is the golden urn, a lot-drawing procedure imposed by the Qing court in 1793, whose historical use was intermittent and whose relevance is contested by Tibetan authorities.
The case that shows what this means in practice is the Panchen Lama. In 1995 the Dalai Lama recognised Gedhun Choekyi Nyima, then six years old. The boy and his family were taken into Chinese custody within days and have not been seen publicly since; the Chinese government has stated he is alive and wishes to be left alone. The state installed a different candidate, Gyaincain Norbu, who is not recognised by most Tibetan Buddhists.
The stake is the next Dalai Lama, and both sides know it. The Dalai Lama has said the institution may not continue after him, that any successor recognised by China should not be accepted, and that the decision rests with the Tibetan people. Nothing about the succession is agreed, and the office described in this entry is one whose future is a matter of open political conflict rather than settled religious procedure.